Bearing or azimuth between 2 sets latitudes longitudes

DAX DAX Calculations
1

Hi,
I need a DAX formula to calculate the bearing in degrees between 2 sets of latitude/longitude points, my distance DAX is working fine, but for bearing I need the ATAN2 formula which is available in PowerQuery but not in DAX.
Would appreciate your help.
Paul

2

@Paul,

See if this works for you:

https://community.powerbi.com/t5/Quick-Measures-Gallery/ATAN2/td-p/963263

  • Brian
1 Like
3

Thank you @Brian, I have tried this one, but did not get the expected results. To be quite honest, this level of trigonometry is beyond my comfortzone :grinning:
Paul

4

@Paul,

Yeah, beyond mine too.

The guy who developed this formula, Greg Deckler, is a DAX superstar on the Microsoft PBI forum, and is really responsive to questions. Iā€™d recommend posting the unexpected results you got there and asking if he can help you resolve the issue.

  • Brian
5 
In the meantime this has been solved, thanks to all for thinking with me.
    Solution:
                    Bearing (Degrees) = 
                        VAR __FromCity = SELECTEDVALUE('From City'[City])
                        VAR __ToCity = SELECTEDVALUE('To City'[City])
                        VAR __FromLat = RADIANS(LOOKUPVALUE('Table'[Latitude];'Table'[City];__FromCity))
                        VAR __ToLat = RADIANS(LOOKUPVALUE('Table'[Latitude];'Table'[City];__ToCity))
                        VAR __FromLong = RADIANS(LOOKUPVALUE('Table'[Longitude];'Table'[City];__FromCity))
                        VAR __ToLong = RADIANS(LOOKUPVALUE('Table'[Longitude];'Table'[City];__ToCity))
                        VAR __distanceLong = (__ToLong - __FromLong)
                        VAR __y = COS(__ToLat) * SIN(__distanceLong)
                        VAR __x = COS(__FromLat) * SIN(__ToLat) - SIN(__FromLat) * COS(__ToLat) * COS(__distanceLong)
                        VAR __atan2 = 
                            SWITCH(
                                TRUE();
                                __x > 0; ATAN(__y/__x);
                                __x < 0 && __y >= 0; ATAN(__y/__x) + PI();
                                __x < 0 && __y < 0; ATAN(__y/__x) - PI();
                                __x = 0 && __y > 0; PI()/2;
                                __x = 0 && __y < 0; PI()/2 * (0-1);
                                BLANK()
                            )
                    RETURN
                        DEGREES(__atan2)